This invention relates to apparatus for blasting a bulky and large workpiece in an enclosed blasting area with a blasting wheel that is movable in relation to the workpiece.
Convenientlly, bulky and large workpieces, such as containers, boilers, bridge beams, nuclear reactor parts, and the like, are cleaned by air operated blasting nozzles, which are operated manually. An operation of this type is not only very laborious, but it is also very inefficient and is very costly from the time standpoint.
To overcome these inadequacies, other types of blasting operations have been attempted. Efforts have been made to blast workpieces in an enclosed blasting room or enclosure, wherein the walls are equipped with many different centrifugal impellers or blasting wheels, which are arranged to encompass the entire workpiece. In blasting rooms of this character, the workpieces have had to be moved in relation to the walls of the rooms and to the blasting wheels. Due to the substantial number of wheels required and due to the fact that the workpieces have had to be moved, it was necessary to provide large rooms and the overall arrangement was costly. It was also difficult in some instances to blast workpieces of different shapes when using the same room or enclosure with the blasting wheels in stationary locations.
Efforts have been made to move a single blasting wheel over a section of a wall or ceiling of a blasting room or enclosure. This was done to cover larger areas of a workpiece with one blasting wheel and required a room or enclosure that was dimensioned in such a way that one wheel would cover the total length of the workpiece. However, this procedure was completely inadequate to provide the desired quality of blasting for many products of large or irregular shape.